5 - Stroke Flashcards
Define stroke.
Acute focal neurological deficit resulting in cerebrovascular disease and lasting more than 24 hours or causing earlier death
Describe stroke.
- death of brain tissue due to hypoxia
- no local cerebral blood flow which can be due to infarction or haemorrhage
What is a TIA?
- transient ischaemic attack
- temporary ischaemia of brain
- indicative risk of a full stroke
- localised loss of brain function
- recover within 24 hours, usually within 30 mins
What does FAST stand for?
Indicator tool for stroke
F - facial drooping
A - arm weakness
S - speech difficulty
T - time
What are the general risk factors for stroke?
- hypertension
- smoking
- alcohol
- ischaemic heart disease
- AF
- diabetes
What are the different types of stroke?
- infarction
- haemorrhage
- subarachnoid haemorrhage
- venous thrombosis
What is the prevalence of stroke?
- increasing incidence with age
- males > females
- 12% all deaths
What increases the risk of embolic stroke?
- AF
- heart valve disease
- recent MI
What vessels are commonly affected by atheromas that can cause TIAs?
- carotid bifurcation
- ICA
- vertebral artery
What increases the risk of venous thrombosis?
- OCP
- polycythaemia (high haemoglobin)
- thrombophillia
What drugs are used in the prevention of stroke?
Antiplatelets (secondary prevention)
- aspirin
- dipyridamole
- clopidogrel
Anticoagulants (embolic risk)
- warfarin
- apixaban
What surgery is used in the prevention of stroke?
- carotid endarterectomy (remove accumulation of plaque from bifurcation)
- preventative neurosurgery (aneurysm clip, AV malformation correction)
How is stroke investigated using images?
- CT scan (poor for ischaemic)
- MRI (better at visualising early changes)
- MR angiography (visualises brain circulation)
- digital subtraction angiography (DSA, if MRA not available)
What other screening tools are used for investigating stroke?
Assessment of risk factors:
- carotid ultrasound (atherosclerosis)
- cardiac ultrasound (LV thrombus)
- ECG (arrhythmias)
- blood pressure
- diabetes screen
- thrombophillia screen (young patients)
What are the effects on tissue caused by stroke?
- loss of functional brain tissue (cell death, including surrounding tissues if not protected)
- gradual or rapid loss of function
- inflammation in surrounding tissue can recover some function over time
